Yep, when I was reading it again I noticed the same thing even before I saw your reply. The thing is that I wanted "kama" to cover both "musi" and "pilin" and I didn't want to repeat it to say "e musi kama e pilin kama", although perhaps I should indeed have done that. As I wrote it, it's not exactly a new predicate... but perhaps as I wrote it, it's simply wrong.

I think you forgot "e pan" in your second example sentence, by the way. Anyway, I know the principles. Thanks for outlining them, regardless, though.

So to clarify, what I meant to say was,"It's good that you can talk about future musi and pilin in this group."

Actually, I didn't entirely understand how you meant "musi"... I took it as kind of "playful ideas" or something, but it could be that you meant "games" literally and that's what you tend to focus on on this forum (I didn't check). I thought I'd add "pilin" because, well, pretty much whatever you're posting, you'll be sharing your thoughts about it.

Tricky grammatical point. There are (at least) two "and"s in English (and most languages). one that joins two sentences or fuses two sentences so joined and one that indicates mixtures: the difference between "a red and a blue ball" (two balls, each one color) and "a red and blue ball" (one ball, two colors). For the sentential "and", when what is joined are two predicates, the second is marked with a new 'li'. Similarly, when what is joined are two DOs, the second is marked with a new 'e'. But for the mixture "and", 'en' is used in every case. And even for the sentential in cases other than predicates and DOs. But the problem here is a different and more recalcitrant one. We are collapsing two sentences which are the same except that one has the DO 'musi kama' and the other has 'pilin kama', so we are on the sentential track and we can clearly put 'e musi kama e pilin kama' into the common matrix. But there is still some common ground here, which might go into the matrix: 'kama'. If we write 'e musi e pilin kama', however, it may appear that 'kama' modifies only 'pilin', since it seems that a new unit begins at the second 'e'. While this is true, it is not the only truth, for it is equally the case that a unit, "DO" begins with the first 'e' and it groups left (as always), meaning that a modifier after the parts "DO" will modify all of those parts, that is, both DOs. There is no way to force one of these interpretations rather than the other and context may not be much help. But it is the case that 'en' for 'e' is incorrect here.

Actually, I didn't look as closely at some of the other boards as I perhaps should have, and did not yet notice; but you're right, "musi" clearly has that interpretation, there. I thought it might be something like that, but thanks for pointing it out specifically.

Also thank you, janKipo, for the thorough discussion of the case here. Thinking about it now, it makes sense that "kama" could extend over the whole of "e musi e pilin". I guess in this case, I'll just go for the explicit "e musi kama e pilin kama" if I want to make sure there's no ambiguity there.